DESCRIPTION (Taken from the application): The Transgenic Animal and Molecular Core C has been an important and essential component of the program project for over ten years. Core C has three major activities: (1) to design and synthesis transgenes; (2) to establish breeding lines of transgenic mice from transgenic founders provided by the Institutional Transgenic Animal Facility or obtained from external sources; and (3) to maintain and produce experimental lines of mice for project investigators. These mice may bear a specific transgene, a defined targeted allele, a spontaneous mutation or a combination of these produced in a defined breeding experiment.